The finds from Nydam and Illerup are probably of Germanic origin, right? The sites are in Denmark after all, a bit off from Roman territory. Not to say that the Romans and the Germans couldn't use similar spears, and of course any such direct archaeological evidence is much better than speculating on spear lengths based on artistic illustrations.
However, I don't believe the evidence I'm aware of favours spears as longs as 3 metres. These would be exceptionally long for 1-handed spears.
And to reiterate my earlier post concerning the said evidence:
The Classical Dory is usually thought as 2.1-2.4 metres long. This seem somewhat confirmed by the archaeological record, as the remains of a 2.2m Dory have been recovered from a tomb (according to Osprey's Warrior: Greek Hoplite 480-323 BC).
According to a
post from myarmoury.com, the survivng shafts from Nydam ranged between 2.54 and 3.54 metres (diameter usually 2.6cm).
Also, according to a well-quoted
post from RomanArmyTalk, the finds from Illerup measure between 2.23 and 2.74 metres.
According to Wikipedia, the Nydam finds are from 200 to 400 AD and the Illerup finds from 200 to 500 AD. So I guess it's highly possible that Germanic and Roman equipment somewhat mirrored each other during this period, and that the Danish finds indeed reflect practice within the Roman Empire.
However, it is interesting to compare these finds that indicate the spears used (at least the preserved ones) were clearly designed as thrusting spears, and compare this to Tacitus' account in Germania (ca. 100 AD):
Even iron is not plentiful with them, as we infer from the character of their weapons. But few use swords or long lances. They carry a spear [hasta] (framea
is their name for it), with a narrow and short head, but so sharp and easy to wield that the same weapon serves, according to circumstances, for close or distant conflict. As for the horse-soldier, he is satisfied with a shield and spear; the foot-soldiers also scatter showers of missiles each man having several and hurling them to an immense distance, and being naked or lightly clad with a little cloak.
- From
Wikipedia; Tacitus (Germania 6)